code: def get_background_frequency_df(frequency_path=None):
      raise Exception
  
file_path: scattertext/scattertext/frequencyreaders/DefaultBackgroundFrequencies.py
imports: import pkgutil
  from io import StringIO
  import pandas
  from scipy.stats import rankdata
label_desc: Use image node_id 1 for calling the BackgroundFrequencies obj's underlying member method code with example usage: obj.get_background_frequency_df(frequency_path) without return types